Panel fastener

ABSTRACT

An elongate fastener is provided for securing a pair of panels together wherein the panels includes respective bores therein. Each end of the fastener includes an expansible end portion thereon which is arranged to be received within the respective bore. A wedge member is mounted within each expansible end portion for longitudinal sliding movement between a disengaged position and an engaged position wherein the expansible end portions are expanded relative to the disengaged position. An actuator is located centrally between the expansible end portions for pivotal movement about an actuator axis which lies perpendicularly to a longitudinal axis of the fastener. The fastener permits a pair of panels to be mounted with one end of one panel abutted against the other panel wherein the actuator is accessible from a recessed installation aperture on an inner face of one of the panels. The resulting joint is secure while being hidden from view using a one-piece fastener.

FIELD OF THE INVENTION

This application is a continuation-in-part application of U.S.application Ser. No. 09/598,277, filed on Jun. 22, 2000, which hasmatured to U.S. Pat. No. 6,299,397, granted on Oct. 9, 2001.

This invention relates to a fastener for fastening a pair of objectstogether. It has particular application to the coupling of panels, forexample those used in furniture.

BACKGROUND

Various types of fasteners are used for assembly of furniture and thelike wherein it is desirable to make use of a fastener which is strongyet simple and quick to use. This includes the commercial assembly ofcabinets and the like as well as assembly of furniture at the factory byprofessionals. The ready to assemble (RTA) furniture industry is oneparticular example involving furniture which is sold to the customer ina disassembled form that makes use of appropriate fasteners such thatthe customer is able to assemble the furniture in their homes usingconventional tools. Fasteners designed for this use are preferably easyto use by the general public, while being secure and well hidden uponassembly of the RTA furniture.

An example of a fastener for RTA furniture is illustrated in EuropeanApplication No. 0 949 424 to Hafele GmbH &CO. That application disclosesa fastener for use in mounting a pair of panels together wherein thefastener includes a first expansible wedge member arranged to mount in abore in one of the panels and a second expansible wedge member arrangedto mount in a bore in the other panel. An actuator for the wedges islocated at one end of the fastener such that the second wedge member islocated centrally on the fastener and oriented such that upon assembly,an apex of the second wedge member is directed inwardly towards thepanel securing the second wedge member therein. This occurs due to thelocation of the actuator at one end of the fastener which requires bothwedges to be oriented in the same direction in order to make use of acommon actuator. In this orientation, expansion of the second wedgemember causes a wedging action to urge the fastener out of the panelinstead of drawing the panels together. Furthermore, the first andsecond wedge members require different bore sizes in which to bereceived which results in added tooling and manufacturing costs whenforming the panels.

SUMMARY

According to one aspect of the present invention there is provided amethod of joining two objects with respective fastener receiving borestherein, the method comprising:

providing an elongate fastener assembly with opposite ends, the fastenerassembly comprising first and second elongate fastener elements arrangedside by side;

inserting the opposite ends of the fastener assembly into the respectivebores; and

displacing the first and second fastener elements relative to oneanother to expand the ends of the fastener assembly thereby griping thebores.

The movement of the two elements relative to one another thus causes theexpansion of the ends of the fastener assembly for anchoring purposes.

According to another aspect of the present invention there is provided afastener for securing together a pair of opposing objects havingrespective bores therein, the fastener comprising:

an elongate fastener assembly having first and second expansibleportions at respective ends thereof for being slideably received withinthe respective bores;

first and second wedge members mounted adjacent the respective ends ofthe fastener assembly for engagement with the respective first andsecond expansible portions thereof, the wedge members and the respectiveexpansible portions being mounted for sliding movement relative to oneanother in a longitudinal direction of the fastener assembly between adisengaged position and an engaged position wherein the wedge membersare wedged within the respective expansible portions of the fastenerassembly such that the expansible portions of the fastener assembly areexpanded in a radial direction relative to the disengaged position; and

an actuator mounted on the fastener assembly for rotation about anactuator axis extending transversely to the elongate fastener assemblyat a location spaced between the wedge members, the actuator beingcoupled to the wedge members respectively for displacing the wedgemembers relative to the expansible portions between the engaged anddisengaged positions as the actuator is rotated relative to the fastenerassembly.

The expansible portions of the fastener assembly may be mounted forlongitudinal sliding movement relative to one another and coupled to theactuator to be displaced towards one another in moving from thedisengaged position to the engaged position.

The actuator may be a cam mounted for rotation about an actuator axis.Each wedge member may be associated with a cam follower for urging thewedge member into the engaged position as the cam is rotated.

The wedge members may fixed in relation to the fastener assembly and theexpansible portions slideably mounted on the fastener assembly formovement towards each other as the expansible portions are displacedfrom the disengaged position to the engaged position. Alternatively, theexpansible portions may be fixed in relation to the fastener assemblyand the wedge members slideably mounted for movement away from eachother as they are displaced from the disengaged position to the engagedposition.

In one particularly advantageous embodiment, the fastener assembly hastwo elongate elements, each including respective ones of the expansibleportions and the wedge members. The two elements are slideable relativeto one another for displacing the wedge members relative to therespective expansible portions between the disengaged and the engagedpositions.

In another embodiment, a flexible tension member is coupled between thetwo wedge members and the actuator is a rotatable spindle having anaperture through which the tension member is threaded so that rotationof the spindle causes the tension member to be wrapped about thespindle, drawing the wedge members longitudinally towards each other.

The fastener may include a lock for resisting reverse rotation of thespindle and unwinding of the tension member.

The wedge members may be substantially conical in shape, with an innersurface of each expansible portion having a mating conical surface.

According to another aspect of the present invention there is provided afastener for securing together opposing objects having respective borestherein, the fastener comprising:

a pair of elongate members each having a wedge at a first end and anexpansible portion at a second end thereof, the wedge of each memberbeing located adjacent the expansible portion of other member, spacedlongitudinally inward therefrom in a disengaged position, the elongatemembers being slideable relative to one another in a longitudinaldirection of the members from the disengaged position to an engagedposition wherein the wedge of each member is wedged within theexpansible portion of the other member such that the expansible portionsare expanded radially relative to the disengaged position; and

stop means associated with each of the members for engaging therespective objects as the ends of the members are inserted into therespective bores, whereby on displacement of the objects towards oneanother, the objects engage the stop means to displace the expansibleends inwardly towards each other and into the engaged position thereof.

According to a further aspect of the present invention there is providedfastener for coupling two objects with respective fastener receivingbores therein, the fastener comprising an elongate fastener assemblywith opposite ends for insertion into the respective bores in the twoobjects, the assembly including:

first and second elongate elements positioned side by side andrelatively movable between a disengaged position and an engaged positionin which the ends of the fastener assembly are expanded transversely toengage the respective bores; and

a retainer for retaining the first and second elements in the engagedposition.

The retainer is particularly useful in those embodiments where there isno actuator per se incorporated into the fastener, and the relativemovement of the first and second elements of the fastener assembly iscaused either by an external tool that does not form part of thefastener or by engagement of the fastener elements with objects to bejoined as they are moved together. In one such embodiment the twoelements are longitudinally tapered and slide over one another as wedgesas they are longitudinally displaced relative to one another. Thisexpands the lateral dimension of the fastener to engage the bores in thetwo objects being coupled.

In embodiments without an actuator, one of the elements may have atransverse through aperture and the other a cavity confronting theaperture. This allows a lever, for example a screwdriver to be insertedthrough the aperture to engage the cavity so that a prying action willmove the two elements relative to one another.

The retainer may be one or more projections on one of the two elementsand mating recesses in the other element, with the projections havinginclined leading faces to serve as a kind of ratchet mechanism.

In other embodiments, the fastener includes an actuator that is used toseparate the two elements transversely. This may be a screw threadedinto one of the elements and engaging the other. In this case, the twoelements move transversely relative to one another in movement betweenthe disengaged and engaged position. The threaded actuator then servesas the retainer.

According to another aspect of the present invention there is provided afastener for coupling two objects with respective fastener receivingbores therein, the fastener comprising an elongate fastener assemblywith opposite ends for insertion into the respective bores in the twoobjects, the ends being transversely expandable to grip the respectivebores and each end having teeth on the periphery thereof, wherein theteeth are helically oriented ribs.

The helical teeth allow the fastener to be screwed into the bores beforeexpansion of the fastener assembly ends.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings, which illustrate exemplary embodiments ofthe present invention:

FIG. 1 is an isometric view of a first embodiment of the presentinvention shown as it would be installed between a pair of panels to bejoined.

FIG. 2 is a sectional side view of the fastener of FIG. 1 in adisengaged position.

FIG. 3 is a sectional view along the line 3—3 of FIG. 2 in an engagedposition.

FIG. 4 is a side view of a different embodiment of the fasteneraccording to the present invention shown in a disengaged position.

FIG. 5 is a side view of the fastener of FIG. 4 shown in the engagedposition.

FIG. 6 is a partly sectional view along the line 6—6 of FIG. 5.

FIG. 7 is a top plan view of a further embodiment of the presentinvention shown in a disengaged position.

FIG. 8 is a top plan view of the fastener of FIG. 7 shown in an engagedposition.

FIG. 9 is an isometric view of yet another embodiment of the presentinvention.

FIG. 10 is an exploded side view of the fastener according to FIG. 9.

FIG. 11 is a top view along the line 11—11 of FIG. 10.

FIG. 12 is an isometric view of a further embodiment of the fastenershown mounting two panels in an edge to edge configuration.

FIG. 13 is a sectional top view of another embodiment of the fastener.

FIG. 14 is an isometric view of another embodiment of the presentinvention;

FIG. 15 is a axial cross section of the embodiment of FIG. 14;

FIG. 16 is a side elevation of a further embodiment of the presentinvention;

FIG. 17 is a aide view of another embodiment of the present invention;

FIG. 18 is a exploded view of another embodiment of the presentinvention;

FIG. 19 is a side view of the embodiment of FIG. 18;

FIG. 20 is a side view of a fastener assembly end with helical teeth;

FIG. 21 is a partial cross section of a fastener assembly including aninclined cam actuator;

FIG. 22 is an isometric view of a fastener assembly end showing certaintooth configurations;

FIG. 23 is a cross section along line 23—23 of FIG. 22; and

FIG. 24 is a plan view of a one piece molding for use in a fastenerassembly.

FIG. 25 is a plan view of an embodiment that can be installed withouttools.

DETAILED DESCRIPTION

Referring to the accompanying drawings, there is illustrated a fastenergenerally indicated by reference numeral 10. The fastener is for use injoining a pair of opposing panels 12 each having a respective bore 14therein. In the arrangement of FIG. 1, one of the panels shown is anedge bored panel while the opposing surface comprises a face bored panelwherein each bore is arranged to receive an end of the fastener thereinfor joining the panels. This is a typical arrangement when securingready to assembly furniture and the like.

In a first embodiment of the present invention as shown in FIGS. 1through 3, the fastener 10 includes an elongate fastener assembly 16having an expansible portion 18 located at each end of the fastenerassembly. The expansible portions are generally cylindrical extensionsof the fastener assembly having a gripping outer surface 20 for engagingwithin one of the bores 14 of the panels to be joined. The expansibleportions are arranged to be expanded in a radial direction onceinstalled in the respective bores to secure the fastener within thebore.

An inner face 22 of each expansible portion is generally conical inshape, with the inner face 22 of the expansible portions tapered inwardstowards each other. Each expansible portion 18 includes at least onelongitudinally extending expansion slot 24 to permit lateral expansionin a direction indicated by arrows 26.

A pair of wedge members 28 are mounted within the respective expansibleportions 18 for sliding movement therein. Each wedge member 28 isfrustoconical in shape, tapering inwardly towards each other for matingwith the respective inner faces 22 of the expansible portions 18. Asshown in the disengaged position of FIG. 2 the wedge members mate withthe respective expansible portions with the expansible portions being ina relaxed position with a diameter substantially equal to that of thefastener assembly 16. As the wedge members are displaced inwardly asshown in the engaged position of FIG. 3, the members 28 act as wedges toexpand the expansion slots 24 of the respective expansible portions 18thus expanding the portions 18 in the direction of arrow 26.

A tension member 30 in the form of a flexible wire extends between thewedge members 28 and has the wedge members fastened to its oppositeends. In one embodiment the wedge member is hollow and has an apertureat its apex through which the wire is threaded. A ball of greaterdiameter than the aperture is mounted on the end of the wire inside thewedge member.

An actuator is provided in the form of a spindle 32 which is mountedcentrally within the fastener assembly for rotation about a transverseactuator axis 34 substantially perpendicularly to the longitudinal axisof the fastener assembly and to the direction of expansion indicated byarrow 26. An outer end 36 of the spindle includes a conventional socketthereon to be engaged to a screwdriver, for example, to rotate thespindle 32 as desired.

A boss 38 mounts the inner end 40 of the spindle for rotation in theassembly. An aperture is provided in the fastener assembly for receivingthe outer end 36 of the spindle therethrough to permit access to thesocket thereon. In use the outer end 36 of the spindle 32 is alignedwith an installation aperture 42 in an outer surface 44 of one of thepanels 12 to be joined together as shown in FIG. 1.

The spindle 32 includes a diametric aperture 46 through which thetension member 30 is threaded. In this arrangement, as the spindle 32 isrotated, the tension member 30 is wrapped around the spindle 32 as shownin FIG. 3 for tensioning the tension member and drawing the wedgemembers 28 inwardly to expand the respective expansible portions 18.

In use two panels 12 are oriented to be mounted together wherein one ofthe panels includes an installation aperture 42 as shown in FIG. 1. Thefastener is inserted into the respective bores 14 such that the actuatoraxis 34 is aligned with the installation aperture 42 such that thesocket on the outer end of the spindle 32 is accessible once thefastener has been inserted into the respective bores.

Rotation of the spindle as shown in FIG. 3 will displace the wedgemembers from the disengaged position to the engaged position, thusdisplacing two diametric halves of the respective expansible portion 18in the direction indicated by arrow 26 along a diameter thereof whichlies substantially parallel to the surface of the respective panels 12.The compression force which secures the fastener within the respectivebores is thus directed in a plane along the surface of the panel asopposed to expanding the expansible portions in a direction extendingtransversely to the surfaces of the panels 12 which would result inpuckering of the faces of the panels 12 resulting in an undesirablefinish when used on furniture and the like.

The use of a flexible tension member allows unlimited travel of thewedges as opposed to the fixed amount of displacement when using a camactuator. This permits less restrictive tolerances in bore sizes andbore placement when forming panels to be mounted together using thefasteners of the present invention.

In an alternate embodiment as shown in FIGS. 4 through 6 there isprovided an elongate tubular housing 50. The housing includes twopointed ends 52 such that the assembled fastener assembly includes ahollow interior having tapered ends defining respective wedge members 54at respective ends thereof.

A pair of expansible end portions 56 are mounted on the respective endsof the housing for sliding movement relative to the housing and thewedge members 54 which are integrally formed thereon. Each expansibleend portion 56 comprises a cylindrical plug formed in two halves by anexpansion slot 58 extending axially therethrough. The expansion slots 58are aligned with the respective apexes of the wedge members 54 such thatthe wedge members force the two halves of the respective expansible endportions radially outward as the expansible portions 56 are slideablydisplaced inwardly towards each other from a disengaged position withthe wedge members to an engaged position therewith. The expansible endportions are thus expanded primarily in a radial direction indicated byarrow 60. The expansible end portions also include ridges 62 thereon toincrease the gripping force of the ends of the fastener within therespective bores similarly to the first embodiment.

An actuator in the form of a spindle 64 is mounted centrally within thehousing for rotation about an actuator axis 66 which is perpendicular tothe longitudinal axis of the fastener assembly as well the directionindicated by arrow 60. The spindle 64 includes a raised circularprotrusion 68 at each end thereof to be received within respectivemounting apertures in the housing 50 for rotatably mounting the spindle64 thereon. The spindle further includes a pair of axially spaced anddiametrically opposed cams 70, each associated with a respectiveexpansible end portion 56 for displacing the expansible end portionsbetween the respective disengaged and engaged positions as the spindle64 is rotated.

A pair of links 72 are coupled between the respective cams 70 and theassociated expansible end portions 56. Each link includes an inner endhaving an opening therein which defines a cam follower 74 receiving acorresponding one of the cams 70 therein. An outer end of each link 72couples the two halves of the respective expansible end portion thereonat a respective base thereof such that the two halves are resilientlycoupled together. The links 72 act as tension members between theexpansible end portions and the cams 70 for pulling the expansible endportions over the wedges into the engaged position as shown in FIG. 6when the cams 70 are rotated. A portion of the opening of each inner endof the links which faces the expansible end portion associated therewithis arranged to engage the corresponding cam 70 wherein the cam has anincreasing radial dimension at a point of contact as it is rotated fromthe disengaged to the engaged positions so as to pull the expansible endportions inward.

In use the fastener is installed into a pair of panels as described withreference to FIG. 1 for producing a tight fitting joint therebetween. Inthis particular arrangement, as the spindle 64 is rotated by a socket onone end thereof, the expansible end portions are pulled inward towardseach other as they are simultaneously expanded for pulling the surfaces12 to be mounted together towards each other while the expansible endportions are gripped within the respective bores 14 resulting in aparticularly secure and tightened joint.

A third embodiment of the present invention is illustrated in FIGS. 7and 8. An elongate tubular housing 80 is provided having integralexpansible end portions 82. Like the previous embodiment, the expansibleend portions are formed in two halves separated by a longitudinalexpansion slot 84. The two halves of the expansible end portions areresiliently coupled together at their respective inner ends by thehousing 80. An inner end 86 of each expansion slot 84 is generallytriangular in shape having an outwardly extending apex which taperstowards an outer end of the respective slot. The inner ends 86 of therespective expansion slots 84 are thus arranged to each receive atriangular shaped wedge member 88 therein wherein the wedge members areoriented with outwardly extending apices so as to mate with the innerends of the respective expansion slots.

An actuator in the form of a spindle 90 is provided similarly to theprevious embodiment of FIGS. 4 through 6. A pair of links members 92 arecoupled between respective cams on the spindle 90 and the respectivewedge members 88 so as to slideably displace the wedge members 88 in alongitudinal direction within the respective expansion slots 84. As thespindle 90 is rotated, the cams thereon engage a portion of an openingin the inner ends of the respective link members 92 which faces awayfrom the wedge member 88 associated therewith. Thus as the cams arerotated the cams push the wedges outwardly from the disengaged positionto the engaged position for resiliently deforming the expansible endportions radially outward in a direction substantially perpendicular toan axis of the spindle 90.

In this arrangement rotation of a centrally located actuator acts toexpand respective ends of the fastener assembly within respective boresin a pair of mating panels without drawing the expansible end portionsinwardly such that the fastener assembly is substantially equal inlength in both the engaged and disengaged positions thereof.

A further embodiment of the present invention is illustrated in FIGS. 9through 11 wherein the fastener 10 includes a fastener assembly havingfirst and second longitudinally extending elements 100 and 102 mountedfor longitudinal sliding movement with respect to one another. The firstand second elements 100 and 102 of the fastener assembly includeintegral first and second expansible end portions 104 and 106respectively at opposing ends of the fastener assembly. Each expansibleend portion comprises a cylindrical plug having a longitudinallyextending expansion slot 108 extending therethrough to permit expansionthereof in a direction indicated by arrow 110.

The inner ends 112 of the expansion slots 108 are triangular in shapehaving an outwardly extending apex such that each slot 108 is taperedtowards an outer end thereof.

First and second wedge members 114 and 116 are positioned adjacent theinner ends of the expansion slots 108 of the respective first and secondexpansible end portions 104 and 106. Each wedge member 114 and 116 is abell shaped member which tapers outwardly for mating with the respectiveinner ends 112 of the respective expansion slots 108. An opening 120adjacent the inner end 112 of each expansion slot receives thecorresponding wedge member therein in a disengaged position whichpermits the two halves of the expansible end portions to remain in arelaxed position having substantially the same diameter as the assembledcylindrical fastener assembly. Sliding each wedge member longitudinallyoutward relative to the respective expansible end portion forces thewedge member into the expansion slot 108 thus expanding the expansibleend portions radially outward in the direction indicated by arrow 110. Apair of levers 121 are formed integrally within the fastener assembly oneach side of the openings 120 for mounting the respective halves of theexpansible portions thereon such that an inner end of the lever acts asa pivotal mount when flexed as the expansible portions are expanded. Theexpansible portions are thus displaced in an arc about the inner end ofeach lever 121 as they are expanded into the engaged position.

The first wedge member 114 is mounted on an inner end of the second half102 of the fastener assembly for sliding movement therewith relative tothe first half of the fastener assembly 100. Similarly, the second wedgemember 116 is mounted on the inner end of the first half 100 of thefastener assembly for sliding movement therewith relative to the secondhalf 102 of the fastener assembly. The wedge members are thus displacedinto and out of the respective expansion slots 108 by sliding the twoelements of the fastener assembly relative to one another.

An actuator in the form of a spindle 122 is rotatably mounted on thefastener assembly between the ends thereof but offset towards one endfor rotation about an actuator axis 123 extending perpendicularly to alongitudinal axis of the fastener assembly as well as beingperpendicular to the direction indicated by arrow 110. Raised circularprotrusions 124 extend axially from the ends of the spindle 122 to bereceived in respective ones of two longitudinal slots 126 located in therespective halves of the fastener assembly. The slots 126 permitlongitudinal sliding movement therebetween while securing the spindletherein for rotary movement. A socket 128 is located at one end of thespindle.

The spindle 122 carries a pair of axially spaced and diametricallyopposed cams 130. Each cam 130 is received within a corresponding recess132 located in the respective inner face of the respective half of thefastener assembly 100 and 102 associated therewith. Each recess 132 thusdefines a cam follower surface for engaging the respective cam 130associated therewith. The cam profile is arranged to have an increasingradial dimension at a point of contact with the recess 132 as the cam isdisplaced from the disengaged to the engaged positions for displacingthe halves of the fastener assembly relative to one another. Each recess132 includes a notch 134 in a cam follower surface thereof such that thecam is permitted to rotate past the notch 134 when displaced from thedisengaged to the engaged position. Once the cam has been rotated pastthe corresponding notch 134 however, rotation in the reverse directionfrom the engage position to the disengage position is restricted by thenotch which thus acts as a stop.

A longitudinally extending protrusion 136 is mounted along the innerface of the first element 100 of the fastener assembly and is arrangedto be received in a longitudinally extending groove 138 located in aninner face of the second element 102 of the fastener assembly. Thegroove 138 is longer than the protrusion 136 to permit longitudinalsliding movement therebetween while providing torsional support betweenthe first and second elements of the fastener assembly.

The first and second elements 100 and 102 of the fastener assemblyinclude a central portion of reduced diameter providing a groovereceiving an O-ring 140 therein or any other suitable clip for securingthe elements together. The O-ring 140 snugly secures the first andsecond elements of the fastener assembly together while permittinglongitudinal sliding movement therebetween. The section of reduceddiameter of the fastener assembly permits the O-ring 140 to be recessedbelow an outer surface of the fastener assembly.

A stop 142 in tie form of an annular flange is located at the inner endof one of the expansible end portions for the purposes of engaging theobject in which the fastener is to be mounted and limiting penetrationof the end into the bore in the object.

The expansible portions each include a plurality of teeth 144 extendingradially outward. The teeth have penetrating free edges 146 at theirperipheries such that the fins penetrate into the inner surfaces of thebores when the expansible portions are expanded.

In this arrangement rotation of the spindle 122 causes the cams 130 toengage the cam follower surfaces of the respective recesses 132 to slidethe first and second halves 100 and 102 of the fastener assemblylongitudinally inward such that the wedge members 114 and 116 areengaged within the respective expansion slots 108 to expand theexpansible end portions along a plane perpendicular to the axis of therotary cam 122 while simultaneously pulling the respective expansibleend portions inwards towards each other to provide a force which pullstogether a pair of opposing surfaces to be mounted together. The stop142 assists in initially positioning one of the expansible end portionswithin the respective bore. Furthermore the penetration of the teeth 144into the respective bores secures portions of the panel between adjacentteeth as opposed to only frictionally engaging the inner surface of therespective bores receiving the expansible portions therein. The addedgripping force ensures the panels are sufficiently drawn together uponassembly of the fastener with the panels.

A further embodiment is illustrated in FIG. 12 wherein a pair of edgebored panels 160 are shown being assembled by the fastener 10. Thefastener of FIG. 12 includes a fastener assembly having two longitudinalhalves 162 similar to the embodiment of FIGS. 9 through 11 wherein thereis provided an expansible portion at one end and a wedge member at theother end of each half of the fastener assembly. The halves 162 arelongitudinally slideable relative to one another for co-operation of thewedge members with the respective expansible portions as describedabove.

The actuator in the embodiment of FIG. 12 comprises a catch 164 whichextends radially outward from an outer periphery of one half of thefastener assembly. The catch 164 acts as a stop arranged to engage anedge 166 of one of the panels for expanding the expansible portions intothe engaged position as the panels are displaced towards one another.The expansible portion opposite the catch bottoms out in the opposingbore such that the expansible portions are displaced into the engagedposition as the panels are pushed together.

A release aperture 168 is mounted in one of the panels for alignmentwith one of the wedge members when the panels are coupled together suchthat the wedge member may be released from the corresponding expansibleend portion by insertion of a tool through the aperture to engage thewedge member. The fastener according to FIG. 12 is thus selectivelyseparable from the panels by using a conventional or screwdriver or thelike.

In varying arrangements of the embodiment of FIG. 12 there may beprovided a catch on both halves of the fastener assembly or theexpansible ends may be arranged to bottom out within the respectivebores. In either arrangement the panels engage the halves of thefastener assembly respectively to push them together as the panels arepushed together.

In a further embodiment as illustrated in FIG. 13, the fastener 10comprises a tubular housing 170 having expansible end portions 172 withrespective wedge members 174 mounted therein similar to those describedin the first embodiment. An actuator 176 is further provided in the formof a spindle having cams thereon as described above. A pair of linkmembers couple the respective wedge members 174 to the actuator whereinone of the link members comprises a sleeve 178 and the other link membercomprises a rod 180 which is arranged to be slideable received withinthe sleeve 178.

Referring now to variations of the first embodiment shown in FIGS. 1through 3, the spindle 32 may be a screw which is threaded directly intoor through the fastener assembly into the surrounding bore securing thefastener therein. Further arrangements of the pivotal mount 38 are alsopossible to assist in locking the spindle in place once rotated. Thismay include a rubber mount, a cam lock, or a ratchet mechanism. Thespindle 32 may further be provided with a spring mechanism to urge thesocket end thereof outwardly beyond an outer surface of the fastenerassembly to assist in alignment with the installation aperture 42 in oneof the panels to be mounted. In yet another arrangement the spindle 32may be free rotating within the fastener assembly or provided with aratchet or clutch mechanism as well as any other arrangement which wouldallow one end to expand first or to allow one end to expand more.

The tension member may comprise any band of material suitable formounting under tension to draw the wedges inwardly while beingsufficiently flexible to be wrapped about the spindle. When mounting thetension member on the wedge members it may be preferable to provide aslot along one side of the wedge members for receiving the tensionmember therethrough for ease of manufacture. Also for ease ofmanufacture it may be preferable to provide a two part fastener assemblyhinged along one longitudinal side thereof for receiving the actuator,the wedge members and the tension member therein. The two part fastenerassembly may be molded as one piece wherein the two halves are hingedtogether by flexing a connecting portion which connects the two halves.

Referring to the embodiment of FIGS. 9 through 11, the actuator may bemodified so as to remain in a fixed longitudinal position relative toone of the halves of the fastener assembly such that only one cam 130 isrequired to engage the other half of the fastener assembly. In thisarrangement, one half of the fastener assembly is longitudinallyslideable relative to the other half of the fastener assembly inresponse to rotation of the actuator as similarly described in theembodiment of FIGS. 9 through 11, however the actuator is simpler indesign. In either variation of the fastener, the fastener assembly andactuator comprise only three parts which are simple to manufacture andreliable in construction.

Referring generally to either embodiment, further modifications includereplacing the actuator with a rack and pinion arrangement wherein thepinion is arranged to rotate about the actuator axis and a pair of racksare provided which are operatively associated with each expansible endportion.

Although it is preferable to make use of a single standardised bore sizeit may be preferable in some instances to have the diameter of oneexpansible portion being greater than the other or to have only one endwhich expands or one end that expands greater than the other. This isparticularly useful for on panels which have been manufactured usingdifferent standardised bore sizes.

The expansible portions may also be formed such that one is longer inlength than the other. Elongating one of the expansible end portions isparticularly useful when gripping into a panel formed of lightweightmaterial wherein a greater contact area between the expansible portionand the inner surface of the bore is desired.

When mounting panels in an edge to edge configuration as illustrated inFIG. 12, it may be useful to offset the actuator towards one end of thefastener assembly while providing a stop in the form of an annularflange about the center of the fastener assembly to position thefastener 10 evenly within both of the panels.

Further modifications to the spindle 32 include providing a lockmechanism such as a ratchet mechanism or a material with a coefficientof friction such as a securely fit rubber socket mounting one end of thespindle therein.

For ease of alignment of two opposing bores and for ease of insertioninto the bores it may be preferable that an outer diameter of thefastener assembly be substantially equal to an outer diameter of theridges surrounding the expansible end portions before expansion thereof.The fastener assembly is thus snugly fit within the bore while theexpansible portions operate as described above. The use of dowels andglue for alignment of the panels is thus not required.

The outer end of the spindle may include any type of screw head orsocket thereon which would permit controlled rotation thereof. Forsimplicity a conventional screw head is preferable such that only theuse of conventional tools is required.

In order to have more control over the expansion of the respective endsof the fastener assembly, two actuators may be provided wherein oneactuator is associated with each expansible end portion of the fastenerassembly. In this arrangement the fastener may first be inserted intoone panel and expanded therein before mounting the second panel on anopposite end of the fastener.

The shape of the wedge members may be generally triangular or bellshaped as well as any other arrangement having a generally diminishingcross section in one longitudinal direction which defines a camming faceoperatively associated with the expansible end portions and theexpansion thereof.

Depending on which particular arrangement or embodiment the fastenercomprises, different selections of materials may be appropriate. Thematerials which form the fastener will generally include zinc castings,steel, plastic or any combination thereof. Any other material whichwould allow the fastener to function effectively would also beappropriate.

Referring once more to the accompanying drawings, and particularly toFIGS. 14 and 15, there is illustrated a fastener 210 for coupling twoobjects which are illustrated as being two furniture panels 212 and 214.The panels 212 and 214 have respective fastener bores 216 and 218 forreceiving the ends of the fastener 210. The fastener is an elongateassembly that includes two elongate elements 220 and 222 arranged sideby side.The assembly has two expandable ends 224 that are portions ofthe respective elements 220 and 222. Each end is separated into twosegments 26 by a diametral slot 228 extending longitudinally through theend. Spaced along the assembly from the end 224 of element 220 is aradially extending stop 229 that limits penetration of the fastener intothe fastener receiving bore 218 as will be discussed more fully in thefollowing. Each end 224 of the assembly has a set of annular teeth 230.Each of the elements 220 and 222 includes a wedge 232 that confronts theslot 228 in the end 224 of the other element.

The element 220 has a transverse through aperture 234 between the wedge232 and the end 224. This aperture confronts a cavity 236 in the element222. To displace the elements 220 and 222 relative to one another alever 238, which may conveniently be in the form of a flat bladescrewdriver, is inserted through the aperture 234 into the cavity 236and is then pivoted to provide a prying action on the two elements,driving the wedges 232 into the slots 228 to expand the ends of thefastener assembly. At the same time, this draws the ends of the assemblytogether so that objects engaged by those ends will be drawn together.

To hold the elements 220 and 222 in the engaged position, with the endsexpanded, the fastener includes a retainer 240. This includes a set ofprojections, shaped as inclined teeth 242 on the elements 220 and a setof mating recesses 244 on the confronting face of element 222. When thetwo elements are displaced to the engaged position, the teeth 242 arecammed into the recesses 244 by their inclined leading faces and areretained in place by their engagement with the recesses. In order thatthe fastener may be disengaged, an unlock opening 246 is formed in theelements 220, in the centre of the teeth and communicating with theaperture 234. A confronting groove 248 is formed in the element 222 sothat the lever 238 can be inserted into the aperture 234 and opening 246to engage the groove 248, so that the two elements can be pried apartwhen necessary.

FIG. 16 illustrates an alternative embodiment of the present inventionwhere the fastener 250 includes two elements 252 and 254 with matingfaces 256 and 258 inclined to the longitudinal extent of the fastener.Element 252 has a transverse through aperture 60 and element 254 aconfronting cavity 262 that are used in conjunction with a lever todisplace the two elements longitudinally relative to one another, withthe two inclined faces sliding along one another to expand thetransverse dimension of the fastener as the elements move from thedisengaged to the engaged position. This embodiment incorporates theretainer mechanism of FIG. 15 for preventing the elements from returninginadvertently from the engaged to the disengaged position.

A further embodiment of the present invention is illustrated in FIG. 17.In that a embodiment, the fastener 266 has two elements 68 and 270parallel to one another. Each element has a set of teeth 272 on each ofits ends. A spacer 274 is connected to element 270 and is engaged by ascrew 276 threaded into a mating bore in element 268. Rotation of thescrew 276 displaces the elements 268 and 270 transversely with respectto one another to enlarge or contract the ends for engaging or releasingthe bores in which they are seated.

A further embodiment of the fastener as illustrated in FIGS. 18 and 19,were the fastener 278 includes two elements 280 and 282, each with adiametrically split, toothed end 284 and a wedge 286 at the opposite endwhich faces towards the end 24. In this embodiment, the wedges work inthe opposite direction from those of the embodiment illustrated in FIG.14, in that they expand the ends of the fastener assembly from the endsof the assembly towards the centre.

FIG. 20 illustrates an expansible end for use on one of the elements ofa fastener like that illustrated in FIG. 14. In this case, the end 288has helical teeth 290 which allow the end to be screwed into an objectto which the fastener is to be connected.

FIG. 21 illustrates a cam mechanism for use in displacing the twoelements 292 and 294 of a fastener between the engaged and disengagedpositions and for retaining the elements in the engaged position. Asillustrated each element has an inclined bore 296 for receiving a cam298. These cams are joined by a shaft 300. The cams and the shaft arerotatable about an inclined axis 302 using a screwdriver engaged in anappropriate screwdriver engaging formation 304 in the end of one of thecams 298. This arrangement makes it convenient to place the actuator camcloser to the intersection between two objects than would otherwise bethe case, that the screwdriver will be inclined away from the junctureof the two parts to be joined.

FIGS. 22 and 23 illustrate an alternative form of the teeth used on theends of the fasteners. As shown, two different tooth configurations, 306and 308 teeth are spaced along the end of the fastener and havedifferent profiles providing projecting, triangular teeth to penetratethe surface of the bore when the fastener has expanded. As illustratedthe stop 310 is larger than the teeth in its radial extent so as toengage the face of the object to limit penetration of the fastener intothe bore.

FIG. 24 illustrates a fastener assembly moulded as one piece. Asillustrated, the assembly 320 includes two elements 322 and 324 joinedby a thin, frangible hinge 326 of plastic material. In use, the twoelements are folded together along the hinge and separated when the twoelements are moved relative to one another two the engaged position.

FIG. 25 illustrates, like FIG. 12, an embodiment of the fastener thatcan be installed without tools. In this embodiment, the fastenerassembly 328 has two elements 330 and 332. Element 330 has an expandableend portion 334 at one end and a radially extending stop 336 at theother. The stop is shaped as an axially extending blade to cut into theface of an object that it engages. The element 332 has an expandable end338. Both expandable ends carry peripheral teeth 340. An actuator 342 ismounted on the expandable end 338, adjacent the inner end. This is aradial stop that engages the surface of an object into which theexpandable end portion 338 is inserted, to limit the depth of insertion.This positioning of the stop or actuator may conveniently be used wherethe bore is on the face of a relatively thin panel, although it is notlimited to use in that environment.

In other embodiments similar to that illustrated in FIG. 25, theactuator 342 may be omitted, and the stop 336 replaced with a flat stopthat also serves as an actuator.

While particular embodiments of the present invention have beendescribed in the foregoing, it is to be understood that the invention isnot limited to those embodiments. Other embodiments within the scope ofthe invention are possible. For example, the configuration of theactuators may vary widely, whether configured as cams, stops, screws orsome other mechanism. Cam designs are particularly variable and may beone-lobed or two lobed, depending on whether one or both ends of thefastener are to move relative to the objects being joined in moving fromthe disengaged position to the engaged position. Stops, both forlimiting the depth of penetration and for use as actuators may havevarious forms, depending on any secondary functions they may have, e.g.anti-rotation, and the nature of the material being joined. Wedges mayalso have different configurations. They may, for example be round insome instances to reduce friction. As will be evident to thoseknowledgeable in the in the art, numerous other modifications arepossible within the scope of the invention. All such embodimentsincorporating such modifications are intended to be included within thescope of the present invention. The invention is to be consideredlimited solely by the appended claims.

1. A fastener for coupling two objects with respective fastenerreceiving bores therein, the fastener comprising an elongate fastenerassembly having an axis in the elongate direction and with opposite endsfor insertion into the respective bores in the two objects, the assemblyincluding: separate first and second elongate elements positioned sideby side and relatively movable between a disengaged position and anengaged position in which both ends of the fastener assembly areexpanded transversely to engage the respective bores; and a retainer forretaining the first and second elements in the engaged position; whereinwhen the fastener element is in the disengaged position, linear motionalong the elongate axis alone, of the first elongate element relative tothe second elongate element causes both ends of the fastener assembly toexpand transversely to the engaged position.
 2. A fastener according toclaim 1 wherein the first and second elements are longitudinally taperedand are longitudinally displaced relative to one another in movementbetween the disengaged and engaged positions.
 3. A fastener according toclaim 1 wherein the first element includes a transverse through apertureand the second element includes a cavity confronting the aperturewhereby a lever may be inserted through the aperture to engage thecavity for displacing the first and second elements between the engagedand disengaged positions.
 4. A fastener according to claim 3 wherein theretainer comprises at least one projection on one of the first andsecond elements and a recess in the other of the first and secondelements for receiving the projection in the engaged position.
 5. Afastener according to claim 1 including an actuator for moving the firstand second elements transversely with respect to one another formovement between the disengaged and engaged positions.
 6. A fasteneraccording to claim 5 wherein the actuator comprises an actuator memberextending transversely between the first and second elements androtatable about a transverse axis to vary the spacing of the first andsecond elements.
 7. A fastener according to claim 6 wherein the retainercomprises the actuator member.
 8. A fastener according to claim 7wherein the actuator member comprises a transverse threaded number and amating thread on one of the first and second elements.
 9. A fasteneraccording to claim 1 wherein one of the ends of the fastener assembly islarger in transverse size than the other.
 10. A fastener according toclaim 1 wherein each end comprises teeth on the periphery thereof, andwherein the teeth are helically oriented ribs, extending outwards fromthe end and wherein the first and second elements being movablelongitudinally relative to one another between a disengaged positionwith the ends spaced apart by a first distance and an engaged positionwith the ends spaced apart by a second distance, less than the firstdistance, and the first and second elements including respective meansresponsive to movement of the first and second elements to the engagedposition for transversely expanding the second and first endsrespectively to engage the respective bore.
 11. A fastener according toclaim 1, wherein the first and second elements being movablelongitudinally relative to one another between a disengaged positionwith the expandable ends spaced apart by a first distance and an engagedposition with the expandable ends spaced apart by a second distance,less than the first distance, and the first and second elementsincluding respective means responsive to movement of the first andsecond elements to the engaged position for transversely expanding thesecond and first expandable ends respectively to engage the respectivebores; and a stop on the first element for engaging one of the objectsto limit the depth of insertion of the first expandable end into therespective bore.
 12. A fastener according to claim 11 including a stopon the second element for engaging the other of the objects to limit thedepth of insertion of the second expandable end into the respectivebore.
 13. A fastener according to claim 12 wherein at least one of thestops comprises an actuator for moving the first and second elementsfrom the disengaged position to the engaged position in response tomovement of the objects towards one another.
 14. A fastener according toclaim 11 including an actuator for moving the first and second elementsfrom the disengaged position to the engaged position.
 15. A fasteneraccording to claim 1 wherein the actuator axis is inclined at an angleless than 90° to the elongate fastener assembly.
 16. A method of joiningtwo objects with respective fastener receiving bores therein, the methodcomprising: providing the elongate fastener assembly of claim 1;inserting the opposite ends of the fastener assembly into the respectivebores; and displacing the first and second fastener elements relative toone another in a linear motion along the elongate axis to expand theends of the fastener assembly thereby griping the bores.